For sanity, I would just make the Dragonfly with 3 vertical stabs as fins. It really isn't much for design.

The Phantom Cruiser could be lengthened more like a Goblin. Might grind down a balsa nose to a 3 sided point though. Two large fins for the wings and two smaller ones top and bottom.

Still have to dig through my boxes to see what parts I even have.
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